Reciprocating compressor

ABSTRACT

A reciprocating compressor is provided that may include a cylinder having a compression space; a piston inserted into the compression space of the cylinder and making a relative reciprocating movement with respect to the cylinder; and a plurality of resonance springs that supports both sides of a member that makes a reciprocating movement, among the cylinder and the piston, in a movement direction. The plurality of resonance springs may be compression coil springs, and at least one of the plurality of resonance springs may be arranged in a direction such that a direction of a side force of the spring does not correspond to a gravitational direction. Since the side force and a force based on self-weight may become zero, sagging of a vibrator due to self-weight may be prevented.

CROSS-REFERENCE TO RELATED APPLICATION(S)

Pursuant to 35 U.S.C. §119(a), this application claims priority to Korean Application No. 10-2012-0115622, filed in Korea on Oct. 17, 2012, the contents of which is incorporated by reference herein in its entirety.

BACKGROUND

1. Field

A reciprocating compressor is disclosed herein.

2. Background

In general, a reciprocating compressor is a device that sucks, compresses, and discharges a refrigerant, as a piston thereof reciprocates (or makes a reciprocating movement) within a cylinder at high speed. The reciprocating compressor may be divided into a connection type reciprocating compressor and a vibration type compressor according to a way in which the piston is driven.

The connection type reciprocating compressor compresses a refrigerant as a piston connected to a rotational shaft of a rotary motor reciprocates. The vibration type reciprocating compressor compresses a refrigerant as a piston connected to a mover of a reciprocating motor vibrates to reciprocate in a cylinder. Embodiments disclosed herein relate to a vibration type reciprocating compressor, and hereinafter, a vibration type reciprocating compressor will be referred to simply as a reciprocating compressor.

FIG. 1 is a cross-sectional view of a related art reciprocating compressor. As illustrated in FIG. 1, in the related art reciprocating compressor 1, a frame 20 may be elastically installed in an inner space 10 a of an airtight shell 10, stators 31 and 32 of a reciprocating motor 30 and a cylinder 41 of a compression device C, which is described hereinafter, may be fixed to the frame 20, a piston 42 coupled to a mover 33 of the reciprocating motor 30, which is described hereinafter, may be inserted into the cylinder 41 and coupled thereto to make a reciprocating movement therein.

A suction pipe 11 connected to an evaporator of a refrigerating cycle apparatus (not shown) may be installed to communicate with the inner space 10 a of the shell 10, and a discharge pipe 12 connected to a condenser of the refrigerating cycle apparatus may be installed in a penetrating manner in a vicinity of the suction pipe 11.

A compression space S1 may be formed in the cylinder 41, a suction flow path F that guide a refrigerant to the compression space S1 may be formed in the piston 42, a suction valve 43 that opens and closes the suction flow path F may be installed in an end of the suction flow path F, and a discharge valve 44 may be installed in or at a front end of the cylinder 41 to open and close the compression space S1 of the cylinder 41.

A plurality of first resonance springs 52 and a plurality of second resonance springs 53 of a resonance spring device 50 may be installed in or at both sides of a spring supporter 51 to induce a resonant movement of the piston 42 at or in both sides of a movement direction of the piston 42.

The plurality of first resonance springs 52 and the plurality of second resonance springs 53 may be compression coil springs and may be arranged in a circumferential direction between a front side of the spring supporter 51 coupled to the mover 33 and the piston 42, and a flange 21, and between a rear side of the spring supporter 51 and a back cover 23 corresponding thereto.

Reference numeral 36 denotes a magnet, reference numeral 45 denotes a valve spring, reference numeral 46 denotes a discharge cover, reference numerals 61 and 62 denote support springs, reference numeral C denotes the compression device, reference numeral M denotes a motor, and reference numeral S2 denotes a discharge space.

In the related art reciprocating compressor, when power is applied to a coil 35 of the reciprocating motor 30, the mover 33 of the reciprocating motor 30 may make a reciprocating movement. Then, the piston 42 coupled to the mover 33 may make a reciprocating movement at high speed within the cylinder 41 due to the plurality of first resonance springs 52 and the plurality of second resonance springs 53 to suck a refrigerant into the shell 10 through the suction pipe 11. The refrigerant in the inner space 10 a of the shell 10 may be sucked into the compression space S1 through the suction flow path F of the piston 42, and when the piston 42 makes a forward movement, the refrigerant may be discharged from the compression space S1 and move to a condenser (not shown) of the refrigerating cycle apparatus through the discharge pipe 12. These sequential processes may be repeatedly performed.

As the plurality of first resonance springs 52 and the plurality of second resonance springs 53 may be configured as compression coil springs, when the plurality of resonance springs 52 and 53 expand and contract, a side force or torsion moment may be generated. Thus, in the related art, as illustrated in FIG. 2, the plurality of first resonance springs 52 and the plurality of second resonance springs 53 are provided and arranged in a circumferential direction and end turns 52 a and 53 a of the resonance springs adjacent in the circumferential direction face one another and are positioned at a same distance from a center OP of the piston 42, so that the side force or torsion moment may be canceled out.

However, in the related art reciprocating compressor, although the end turns 52 a and 53 a of the plurality of resonance springs 52, 53 are arranged such that the side force and torsion moment, which may be generated as the plurality of first resonance springs 52 and the plurality of second resonance springs 53 contract and expand, are canceled out, sagging of the piston 42 due to self-weight thereof in terms of characteristics of the compression coil springs may not be sufficiently resolved, generating friction loss and abrasion in a particular portion with respect to the cylinder 41 when the piston 42 reciprocates. In particular, when the piston 42 moves backward for a sectional stroke, a rear side of the piston 42 may go down so as to be sloped, further increasing the friction loss and abrasion between the piston 42 and the cylinder 41.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be described in detail with reference to the following drawings in which like reference numerals refer to like elements, and wherein:

FIG. 1 is a vertical cross-sectional view of a related art reciprocating compressor;

FIG. 2 is a schematic view illustrating an arrangement of resonance springs of the reciprocating compressor of FIG. 1 in a circumferential direction;

FIG. 3 is a schematic view illustrating a phenomenon in which a piston sags due to the arrangement of the resonance springs of FIG. 2;

FIG. 4 is a schematic view illustrating an example in which a plurality of resonance springs are arranged in a circumferential direction such that end turns thereof face in a direction opposite to a gravitational direction in a reciprocating compressor according to an embodiment;

FIG. 5 is a schematic view illustrating an arrangement of the resonance springs of FIG. 4;

FIGS. 6 through 8 are schematic views illustrating an arrangement of the resonance springs of FIG. 4 according to another embodiment; and

FIG. 9 is a schematic view illustrating a straightness of a piston based on the arrangement of the resonance springs of FIGS. 4 and 5.

DETAILED DESCRIPTION

Description will now be given in detail of embodiments, with reference to the accompanying drawings. For the sake of brief description with reference to the drawings, the same or equivalent components will be provided with the same reference numbers, and description thereof will not be repeated.

Hereinafter, a reciprocating compressor according to embodiments will be described in detail with reference to the accompanying drawings.

Referring to FIG. 1, in the reciprocating compressor according to this embodiment, frame 20 may be installed to be elastically supported by a plurality of support springs 61 and 62 as described hereinafter in inner space 10 a of shell 10, motor M to generate a reciprocating force may be fixedly coupled to one side of the frame 20, and compression device C may be disposed between the frame 20 and the motor M to compress a refrigerant upon receiving the reciprocating force from the motor M.

The inner space 10 a of the shell 10 may be hermetically closed or sealed, suction pipe 11 may be connected to a wall of one side of the shell 10 to guide a refrigerant of a refrigerating cycle apparatus to the inner space 10 a of the shell 10, and discharge pipe 12 may be installed in a penetrating manner in the one side of shell 10 adjacent to the suction pipe 11 in order to discharge a refrigerant compressed in compression space S1 of cylinder 41 as described hereinafter to the refrigerating cycle apparatus. The plurality of support springs 61 and 62 may be installed on or at a bottom of the shell 10, and the motor M and the compression device C, as well as the frame 20, may be elastically supported by the plurality of support springs 61 and 62, such that they are spaced apart from the bottom of the shell 10 with a predetermined interval therebetween.

Reciprocating motor 30 forming the motor M may include outer stator 31 coupled to the frame 20, inner stator 32 disposed at an inner side of the outer stator 31 with a predetermined gap therebetween and coupled to the frame 20, and mover 33 disposed in a gap between the outer stator 31 and the inner stator 32, having magnet 36 corresponding to coil 35, and reciprocating in a direction of magnetic flux induced by the magnet 36 and the coil 35.

The compression device C may include the cylinder 41 insertedly coupled in the frame 20, piston 42 inserted in the cylinder 41 in a reciprocating manner to compress a refrigerant, and resonance device 50 coupled to the piston 42 to guide a resonant movement of the piston 41.

The cylinder 41 may have a cylindrical shape and insertedly coupled to the frame 20, and discharge valve 44 may be detachably installed in or at a front end of the cylinder 41 to open and close the compression space S1. An inner circumferential surface of the cylinder 41 may form a bearing surface with the piston 42, which may be made of cast iron, and thus, the cylinder 41 may be made of cast iron or a material having a hardness higher than at least that of the frame 20 in order to prevent the cylinder 41 from being abraded by the piston 42.

The piston 42 may have suction flow path F, through which a refrigerant may be sucked into the compression space S1 of the cylinder 41, and suction valve 43 may be installed in or at a front end of the piston 42 to open and close the suction flow path F. The piston 42 may be made of a material the same as that of the cylinder 41 or may be made of at least a material having a hardness similar to that of the piston 42 in order to reduce abrasion with respect to the cylinder 41.

The resonance device 50 may include spring support 51 coupled to the piston 42, and the plurality of first resonance springs 52 and the plurality of second resonance springs 53 installed in front of or behind the spring supporter 51. A single first resonance spring 52 and a single second resonance spring 53 may be provided, or as shown, a plurality of first resonance springs 52 and a plurality of second resonance springs 53 may be provided.

The same reference numerals are used for the same components as those of the related art.

Operational effects of the reciprocating compressor according to embodiments are as follows.

When power is applied to the coil 35 of the reciprocating motor 30, magnetic flux may be formed between the outer stator 31 and the inner stator 32. Then, the mover 33 disposed in the gap between the outer stator 31 and the inner stator 32 may move in a direction of the magnetic flux and continuously reciprocate due to the resonance device 50. Then, the piston 42 coupled to the mover 50 may reciprocate within the cylinder 41 to repeatedly perform a series of processes of sucking, compressing, and discharging a refrigerant.

The resonance springs 52 and 53 may be compression coil springs, which may greatly deform in a horizontal direction. Thus, when the piston 42 reciprocates, in particular, when the piston 42 performs a sucking stroke, a rear side of the piston 42 may be released from the cylinder 41 and sag, and thus, the piston 42 may slope and collide with the cylinder 41 to cause friction loss and abrasion. Thus, the resonance springs 52 and 53 may be arranged such that end turns 52 a and 53 a of surfaces supported by the piston 42 face in a direction opposite to a gravitational direction to reduce sagging of the piston 42.

FIG. 4 is a schematic view illustrating an example in which a plurality of resonance springs are arranged in a circumferential direction such that end turns thereof face in a direction opposite to a gravitational direction in a reciprocating compressor according to an embodiment. As illustrated in FIG. 4, a plurality of the first resonance springs 52 and a plurality of the second resonance springs 53 may be arranged to be spaced apart from one another in the circumferential direction, respectively. The plurality of first resonance springs 52 may be arranged in a vertical direction (i.e., a side of a gravitational direction and an opposite side of the gravitational direction) on the basis of or with respect to the piston 42, and the second resonance springs 53 may be arranged in a horizontal direction on the basis of or with respect to the piston 42. Accordingly, the plurality of first resonance springs 52 and the plurality of second resonance springs 53 may be alternately arranged at 90° intervals.

Pairs of first resonance springs 52 may be arranged in up and down directions and pairs of the second resonance springs 53 may be arranged in left and right directions.

As illustrated in FIG. 5, the plurality of first resonance springs 52 and the plurality of second resonance springs 53, which may be configured as compression coil springs, may be arranged such that end turns of the pairs of resonance springs are symmetrical on the basis of or with respect to a vertical line CL of the piston 42 in order to cancel out a side force and torsion moment thereof.

For example, first resonance springs (hereinafter, referred to as ‘lower resonance springs’) 521 positioned in or at a lower side of the piston 42 within the shell 10 in the gravitational direction may be arranged such that end turns 521 a thereof do not face in the gravitational direction, but rather, in a direction opposite to the gravitational direction. The first resonance springs 52 may be installed to be positioned at the same distance from a center O_(p) of the piston 42, such that the end turns 521 a of the lower resonance springs 521 are closer to the center O_(p) of the piston 42 than end turns 522 a of resonance springs (hereinafter, referred to as ‘upper resonance springs’) 522 in or at the opposite side to the gravitational direction.

A vertical line C_(L1) connecting the end turn 521 a of one lower resonance spring 521 to the center Os of the resonance spring 521 and a vertical line C_(L1) connecting the end turn 521 a of the other lower resonance spring 521 positioned on the other side with respect to the center O_(p) of the piston to the center O_(s) of the resonance spring 521 may be parallel.

A horizontal line C_(L2) connecting the end turns 522 a of the upper resonance springs 522 may be arranged at a position perpendicular to the vertical line C_(L). Accordingly, a vibrator including the piston 42 may be effectively prevented from sagging due to self-weight according to an increase in a support load of the lower resonance spring 521.

The upper resonance springs 522 may be arranged such that the end turns 522 a thereof are positioned to be horizontal with respect to the center O_(s) of the springs, and the lower resonance springs 521 may be arranged such that the end turns 521 a thereof are higher than the center O_(s) of the springs (i.e., at the opposite side to the gravitational direction).

As illustrated in FIG. 6, the end turns 521 a of the lower resonance springs 521 may be arranged to be positioned in virtual lines C_(L3) connecting the center O_(s) of each of the resonance springs and the center O_(p) of the piston 42, or as illustrated in FIG. 7, the end turns 521 a of the lower resonance springs 521 may be arranged to face at about ±45° upwardly such that virtual lines C_(L4) passing through the center O_(s) of each of the resonance springs 521 meet vertical lines below the center O_(p) of the piston 42. Also, in this case, like the foregoing embodiment, the vibrator including the piston 42 may be effectively prevented from sagging due to self-weight according to an increase in a support load of the lower resonance spring 521.

As in the foregoing embodiments, the lower resonance springs 521 may be arranged such that the end turns 521 a thereof are positioned to be different from the end turns 522 a of the upper resonance springs 522, or alternatively, the lower resonance spring 521 and the upper resonance spring may be arranged such that the end turn 521 a and the end turn 522 a are symmetrical. That is, the end turn 521 a of the lower resonance spring 521 and the end turn 522 a of the upper resonance spring 522 may positioned to be aligned with the center O_(p) of the piston 42. Also, in this case, like the foregoing embodiment, the vibrator including the piston 42 may be effectively prevented from sagging due to self-weight according to an increase in a support load of the lower resonance spring 521. Further, the piston 42 may be prevented from being excessively lifted due to misassembling of the lower resonance springs 52 or for any other reasons, enhancing straightness of the piston 42.

Thus, although the resonance springs inducing a resonant movement of the vibrator including the piston are configured as compression coil springs, a side force and a force based on or due to self-weight may become zero, thereby reducing sagging of the vibrator due to self-weight of the vibrator and enhancing straightness of the piston in reciprocating movement, whereby friction loss and abrasion between the cylinder and the piston may be prevented.

Embodiments disclosed herein provide a reciprocating compressor in which, when resonance springs inducing a resonant movement of a piston are configured as compression coil springs, a side force or torsion moment, which may be generated in terms of characteristics of the resonant springs, may be canceled out and the piston prevented from sagging to thus enhance a straightness of the piston.

Embodiments disclosed herein provide a reciprocating compressor that may include a cylinder having a compressive or compression space; a piston inserted into the compressive space of the cylinder and making a relative reciprocating movement with respect to the cylinder; and a plurality of resonance springs that supports both sides of a member that makes a reciprocating movement, among the cylinder and the piston, in a movement direction. The resonance springs may be configured as compression coil springs and at least one of the resonance springs may be arranged in a direction such that a direction of side forces of the spring does not correspond to a gravitational direction.

Embodiments disclosed herein provide a reciprocating compressor that may include a cylinder having a compression space; a piston inserted into the compression space of the cylinder and making a relative reciprocating movement with respect to the cylinder; and first resonance springs configured as compression coil springs that elastically supporting one side of the spring and second resonance springs configured as compression coil springs that elastically support the other side of the piston. The first resonance springs may be arranged in a vertical direction on a basis of a center of the piston, the second resonance springs may be arranged in a horizontal directon on the basis of the center of the piston, and lower first resonance springs, among the first resonance springs, may be arranged in a direction such that a direction of side forces of the springs do not correspond to a gravitational direction.

The foregoing embodiments and advantages are merely exemplary and are not to be considered as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.

As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be considered broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.

Any reference in this specification to “one embodiment,” “an embodiment,” “example embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art. 

What is claimed is:
 1. A reciprocating compressor, comprising: a cylinder having a compression space; a piston inserted into the compression space of the cylinder to make a relative reciprocating movement with respect to the cylinder; and a plurality of resonance springs that supports both sides of one of the cylinder or the piston, in a movement direction, wherein the plurality of resonance springs comprise a plurality of compression coil springs and at least one of the plurality of resonance springs is arranged in a direction such that a direction of a side force of the spring does not correspond to a gravitational direction.
 2. The reciprocating compressor of claim 1, wherein an end turning direction of an end turn of the at least one of the plurality of resonance springs does not correspond to the gravitational direction.
 3. The reciprocating compressor of claim 1, wherein an end turning direction of at least one lower resonance spring of the plurality of resonance springs, which is positioned at a lower side with respect to a center of the one of the cylinder or the piston, does not correspond to the gravitational direction.
 4. The reciprocating compressor of claim 3, wherein the end turn of the at least one lower resonance spring is positioned to be aligned with the center of the one of the cylinder or the piston.
 5. The reciprocating compressor of claim 3, wherein two lower resonance springs of the plurality of resonance springs are provided at the lower side of the one of the cylinder or the piston, and end turns of the two lower resonance springs are symmetrical with respect to a vertical line that passes through the center of the one of the cylinder or the piston.
 6. The reciprocating compressor of claim 5, wherein virtual lines that connect the end turns of the two lower resonance springs and a center of each of the two lower resonance springs are parallel to a vertical line that passes through the center of the one of the cylinder or the piston.
 7. The reciprocating compressor of claim 5, wherein virtual lines that connect the end turns of the two lower resonance springs and a center of each of the two lower resonance springs are positioned along lines that pass through the center of the one of the cylinder or the piston.
 8. The reciprocating compressor of claim 5, wherein virtual lines that connect the end turns of the two lower resonance springs and the center of each of the two lower resonance springs are positioned along lines that pass through a position lower than the center of the one of the cylinder or the piston.
 9. The reciprocating compressor of claim 1, wherein a plurality of upper resonance springs and a plurality of lower resonance springs are provided with respect to the one of the cylinder or the piston, and the plurality of upper resonance springs and the plurality of lower resonance springs are arranged to be symmetrical with a predetermined interval therebetween with respect to a vertical line that passes through a center of the one of the cylinder or the piston.
 10. The reciprocating compressor of claim 9, wherein a space between the plurality of lower resonance springs is smaller than a space between the plurality of upper resonance springs.
 11. A reciprocating compressor, comprising: a cylinder having a compression space; a piston inserted into the compression space of the cylinder to make a relative reciprocating movement with respect to the cylinder; and a plurality of first resonance springs comprising compression coil springs that elastically support a first side of the piston and a plurality of second resonance springs comprising compression coil springs that elastically support a second side of the piston, wherein the plurality of first resonance springs are arranged in a vertical direction with respect to a center of the piston, wherein the plurality of second resonance springs is arranged in a horizontal direction with respect to the center of the piston, and wherein lower first resonance springs, among the plurality of first resonance springs, are arranged in a direction such that a direction of a side force of the lower first resonance springs do not correspond to a gravitational direction.
 12. The reciprocating compressor of claim 11, wherein end turn directions of end turns of the plurality of first lower resonance springs do not correspond to the gravitational direction.
 13. The reciprocating compressor of claim 12, wherein two lower first resonance springs are provided at a lower side of the piston, and the end turns of the two lower first resonance springs are symmetrical with respect to a vertical line that passes through the center of the piston.
 14. The reciprocating compressor of claim 13, wherein virtual lines that connect the end turns of the two lower first resonance springs and a center of each of the two lower first resonance springs are parallel to a vertical line that passes through the center of the piston.
 15. The reciprocating compressor of claim 13, wherein virtual lines that connect the end turns of the two lower first resonance springs and the center of each of the two lower first resonance springs are positioned along lines that pass through the center of the piston.
 16. The reciprocating compressor of claim 13, wherein virtual lines that connect the end turns of the two lower first resonance springs and the center of each of the two lower first resonance springs are positioned along lines that pass through a position lower than the center of the piston.
 17. The reciprocating compressor of claim 11, wherein a plurality of upper resonance springs and a plurality of lower resonance springs are provided with respect to the piston, and the plurality of upper resonance springs and the plurality of lower resonance springs are arranged to be symmetrical with a predetermined interval therebetween with respect to a vertical line that passes through the center of the piston.
 18. The reciprocating compressor of claim 17, wherein a space between the plurality of lower resonance springs is smaller than a space between the plurality of upper resonance springs.
 19. A reciprocating compressor, comprising: a cylinder having a compression space; a piston inserted into the compression space of the cylinder to make a relative reciprocating movement with respect to the cylinder; and a plurality of first resonance springs comprising coil springs that elastically support a first side of the piston and a plurality of second resonance springs comprising coil springs that elastically support a second side of the piston, wherein the plurality of first resonance springs are arranged in a vertical direction with respect to a center of the piston, wherein the plurality of second resonance springs is arranged in a horizontal direction with respect to the center of the piston, and wherein lower first resonance springs, among the plurality of first resonance springs, are arranged such that end turn directions of end turns of the lower first resonance springs do not correspond to a gravitational direction. 